devfs_rule.c revision 150150
1100206Sdd/*- 2100206Sdd * Copyright (c) 2002 Dima Dorfman. 3100206Sdd * All rights reserved. 4100206Sdd * 5100206Sdd * Redistribution and use in source and binary forms, with or without 6100206Sdd * modification, are permitted provided that the following conditions 7100206Sdd * are met: 8100206Sdd * 1. Redistributions of source code must retain the above copyright 9100206Sdd * notice, this list of conditions and the following disclaimer. 10100206Sdd * 2. Redistributions in binary form must reproduce the above copyright 11100206Sdd * notice, this list of conditions and the following disclaimer in the 12100206Sdd * documentation and/or other materials provided with the distribution. 13100206Sdd * 14100206Sdd * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15100206Sdd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16100206Sdd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17100206Sdd * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18100206Sdd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19100206Sdd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20100206Sdd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21100206Sdd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22100206Sdd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23100206Sdd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24100206Sdd * SUCH DAMAGE. 25100206Sdd * 26100206Sdd * $FreeBSD: head/sys/fs/devfs/devfs_rule.c 150150 2005-09-15 08:50:16Z phk $ 27100206Sdd */ 28100206Sdd 29100206Sdd/* 30100206Sdd * DEVFS ruleset implementation. 31100206Sdd * 32100206Sdd * A note on terminology: To "run" a rule on a dirent is to take the 33100206Sdd * prescribed action; to "apply" a rule is to check whether it matches 34100206Sdd * a dirent and run if if it does. 35100206Sdd * 36100206Sdd * A note on locking: Only foreign entry points (non-static functions) 37100206Sdd * should deal with locking. Everything else assumes we already hold 38100206Sdd * the required kind of lock. 39100206Sdd * 40100206Sdd * A note on namespace: devfs_rules_* are the non-static functions for 41100206Sdd * the entire "ruleset" subsystem, devfs_rule_* are the static 42100206Sdd * functions that operate on rules, and devfs_ruleset_* are the static 43100206Sdd * functions that operate on rulesets. The line between the last two 44100206Sdd * isn't always clear, but the guideline is still useful. 45100206Sdd * 46100206Sdd * A note on "special" identifiers: Ruleset 0 is the NULL, or empty, 47100206Sdd * ruleset; it cannot be deleted or changed in any way. This may be 48100206Sdd * assumed inside the code; e.g., a ruleset of 0 may be interpeted to 49100206Sdd * mean "no ruleset". The interpretation of rule 0 is 50100206Sdd * command-dependent, but in no case is there a real rule with number 51100206Sdd * 0. 52100206Sdd * 53100206Sdd * A note on errno codes: To make it easier for the userland to tell 54100206Sdd * what went wrong, we sometimes use errno codes that are not entirely 55100206Sdd * appropriate for the error but that would be less ambiguous than the 56100206Sdd * appropriate "generic" code. For example, when we can't find a 57100206Sdd * ruleset, we return ESRCH instead of ENOENT (except in 58100206Sdd * DEVFSIO_{R,S}GETNEXT, where a nonexistent ruleset means "end of 59100206Sdd * list", and the userland expects ENOENT to be this indicator); this 60100206Sdd * way, when an operation fails, it's clear that what couldn't be 61100206Sdd * found is a ruleset and not a rule (well, it's clear to those who 62100206Sdd * know the convention). 63100206Sdd */ 64100206Sdd 65100206Sdd#include "opt_devfs.h" 66100206Sdd 67100206Sdd#include <sys/param.h> 68100206Sdd#include <sys/systm.h> 69100206Sdd#include <sys/conf.h> 70100206Sdd#include <sys/kernel.h> 71100206Sdd#include <sys/malloc.h> 72100206Sdd#include <sys/dirent.h> 73100206Sdd#include <sys/vnode.h> 74100206Sdd#include <sys/ioccom.h> 75150150Sphk#include <sys/sx.h> 76100206Sdd 77100206Sdd#include <fs/devfs/devfs.h> 78100206Sdd 79100206Sdd 80100206Sdd/* 81100206Sdd * Kernel version of devfs_rule. 82100206Sdd */ 83100206Sddstruct devfs_krule { 84100206Sdd SLIST_ENTRY(devfs_krule) dk_list; 85100206Sdd struct devfs_ruleset *dk_ruleset; 86100206Sdd struct devfs_rule dk_rule; 87100206Sdd}; 88100206Sdd 89100206Sdd/* 90100206Sdd * Structure to describe a ruleset. 91100206Sdd */ 92100206Sddstruct devfs_ruleset { 93100206Sdd SLIST_ENTRY(devfs_ruleset) ds_list; 94100206Sdd devfs_rsnum ds_number; 95100206Sdd SLIST_HEAD(, devfs_krule) ds_rules; 96100206Sdd int ds_refcount; 97100206Sdd int ds_flags; 98100206Sdd#define DS_IMMUTABLE 0x001 99100206Sdd}; 100100206Sdd 101100206Sddstatic devfs_rid devfs_rid_input(devfs_rid rid, struct devfs_mount *dm); 102100206Sdd 103100206Sddstatic void devfs_rule_applyde_recursive(struct devfs_krule *dk, 104100206Sdd struct devfs_dirent *de); 105100206Sddstatic void devfs_rule_applydm(struct devfs_krule *dk, struct devfs_mount *dm); 106100206Sddstatic int devfs_rule_autonumber(struct devfs_ruleset *ds, devfs_rnum *rnp); 107100206Sddstatic struct devfs_krule *devfs_rule_byid(devfs_rid rid); 108100206Sddstatic int devfs_rule_delete(struct devfs_krule **dkp); 109130585Sphkstatic struct cdev *devfs_rule_getdev(struct devfs_dirent *de); 110100206Sddstatic int devfs_rule_input(struct devfs_rule *dr, struct devfs_mount *dm); 111100206Sddstatic int devfs_rule_insert(struct devfs_rule *dr); 112100206Sddstatic int devfs_rule_match(struct devfs_krule *dk, struct devfs_dirent *de); 113100206Sddstatic int devfs_rule_matchpath(struct devfs_krule *dk, 114100206Sdd struct devfs_dirent *de); 115150147Sphkstatic void devfs_rule_run(struct devfs_krule *dk, struct devfs_dirent *de, unsigned depth); 116100206Sdd 117100206Sddstatic void devfs_ruleset_applyde(struct devfs_ruleset *ds, 118150147Sphk struct devfs_dirent *de, unsigned depth); 119100206Sddstatic void devfs_ruleset_applydm(struct devfs_ruleset *ds, 120100206Sdd struct devfs_mount *dm); 121100206Sddstatic struct devfs_ruleset *devfs_ruleset_bynum(devfs_rsnum rsnum); 122100206Sddstatic struct devfs_ruleset *devfs_ruleset_create(devfs_rsnum rsnum); 123100206Sddstatic void devfs_ruleset_destroy(struct devfs_ruleset **dsp); 124100206Sddstatic void devfs_ruleset_reap(struct devfs_ruleset **dsp); 125100206Sddstatic int devfs_ruleset_use(devfs_rsnum rsnum, struct devfs_mount *dm); 126100206Sdd 127150150Sphkstatic struct sx sx_rules; 128100206Sddstatic SLIST_HEAD(, devfs_ruleset) devfs_rulesets; 129100206Sdd 130100206Sdd/* 131150147Sphk * Called to apply the proper rules for 'de' before it can be 132100206Sdd * exposed to the userland. This should be called with an exclusive 133100206Sdd * lock on dm in case we need to run anything. 134100206Sdd */ 135100206Sddvoid 136100206Sdddevfs_rules_apply(struct devfs_mount *dm, struct devfs_dirent *de) 137100206Sdd{ 138100206Sdd struct devfs_ruleset *ds; 139100206Sdd 140150150Sphk sx_slock(&sx_rules); 141100206Sdd ds = devfs_ruleset_bynum(dm->dm_ruleset); 142100206Sdd KASSERT(ds != NULL, ("mount-point has NULL ruleset")); 143150147Sphk devfs_ruleset_applyde(ds, de, devfs_rule_depth); 144150150Sphk sx_sunlock(&sx_rules); 145100206Sdd} 146100206Sdd 147100206Sdd/* 148100206Sdd * Rule subsystem SYSINIT hook. 149100206Sdd */ 150125855Sphkstatic void 151125855Sphkdevfs_rules_init(void *junk __unused) 152100206Sdd{ 153100206Sdd struct devfs_ruleset *ds; 154100206Sdd 155150150Sphk sx_init(&sx_rules, "devfsrules"); 156100206Sdd SLIST_INIT(&devfs_rulesets); 157100206Sdd 158100206Sdd ds = devfs_ruleset_create(0); 159100206Sdd ds->ds_flags |= DS_IMMUTABLE; 160100206Sdd ds->ds_refcount = 1; /* Prevent reaping. */ 161100206Sdd} 162100206Sdd 163125855SphkSYSINIT(devfs_rules, SI_SUB_DEVFS, SI_ORDER_FIRST, devfs_rules_init, NULL); 164125855Sphk 165100206Sdd/* 166100206Sdd * Rule subsystem ioctl hook. 167100206Sdd */ 168100206Sddint 169150149Sphkdevfs_rules_ioctl(struct devfs_mount *dm, u_long cmd, caddr_t data, struct thread *td) 170100206Sdd{ 171100206Sdd struct devfs_ruleset *ds; 172100206Sdd struct devfs_krule *dk; 173100206Sdd struct devfs_rule *dr; 174100206Sdd devfs_rsnum rsnum; 175100206Sdd devfs_rnum rnum; 176100206Sdd devfs_rid rid; 177100206Sdd int error; 178100206Sdd 179100206Sdd /* 180100206Sdd * XXX: This returns an error regardless of whether we 181100206Sdd * actually support the cmd or not. 182100206Sdd */ 183100206Sdd error = suser(td); 184100206Sdd if (error != 0) 185100206Sdd return (error); 186100206Sdd 187150150Sphk sx_xlock(&sx_rules); 188100206Sdd switch (cmd) { 189100206Sdd case DEVFSIO_RADD: 190100206Sdd dr = (struct devfs_rule *)data; 191100206Sdd error = devfs_rule_input(dr, dm); 192100206Sdd if (error != 0) 193100206Sdd goto out; 194100206Sdd dk = devfs_rule_byid(dr->dr_id); 195100206Sdd if (dk != NULL) { 196100206Sdd error = EEXIST; 197100206Sdd goto out; 198100206Sdd } 199100206Sdd error = devfs_rule_insert(dr); 200100206Sdd break; 201100206Sdd case DEVFSIO_RAPPLY: 202100206Sdd dr = (struct devfs_rule *)data; 203100206Sdd error = devfs_rule_input(dr, dm); 204100206Sdd if (error != 0) 205100206Sdd goto out; 206100206Sdd 207100206Sdd /* 208100206Sdd * This is one of many possible hackish 209100206Sdd * implementations. The primary contender is an 210100206Sdd * implementation where the rule we read in is 211100206Sdd * temporarily inserted into some ruleset, perhaps 212100206Sdd * with a hypothetical DRO_NOAUTO flag so that it 213100206Sdd * doesn't get used where it isn't intended, and 214100206Sdd * applied in the normal way. This can be done in the 215100206Sdd * userland (DEVFSIO_ADD, DEVFSIO_APPLYID, 216100206Sdd * DEVFSIO_DEL) or in the kernel; either way it breaks 217100206Sdd * some corner case assumptions in other parts of the 218100206Sdd * code (not that this implementation doesn't do 219100206Sdd * that). 220100206Sdd */ 221100206Sdd if (dr->dr_iacts & DRA_INCSET && 222100206Sdd devfs_ruleset_bynum(dr->dr_incset) == NULL) { 223100206Sdd error = ESRCH; 224100206Sdd goto out; 225100206Sdd } 226111119Simp dk = malloc(sizeof(*dk), M_TEMP, M_WAITOK | M_ZERO); 227100206Sdd memcpy(&dk->dk_rule, dr, sizeof(*dr)); 228100206Sdd devfs_rule_applydm(dk, dm); 229100206Sdd free(dk, M_TEMP); 230100206Sdd error = 0; 231100206Sdd break; 232100206Sdd case DEVFSIO_RAPPLYID: 233100206Sdd rid = *(devfs_rid *)data; 234100206Sdd rid = devfs_rid_input(rid, dm); 235100206Sdd dk = devfs_rule_byid(rid); 236100206Sdd if (dk == NULL) { 237100206Sdd error = ENOENT; 238100206Sdd goto out; 239100206Sdd } 240100206Sdd devfs_rule_applydm(dk, dm); 241100206Sdd error = 0; 242100206Sdd break; 243100206Sdd case DEVFSIO_RDEL: 244100206Sdd rid = *(devfs_rid *)data; 245100206Sdd rid = devfs_rid_input(rid, dm); 246100206Sdd dk = devfs_rule_byid(rid); 247100206Sdd if (dk == NULL) { 248100206Sdd error = ENOENT; 249100206Sdd goto out; 250100206Sdd } 251100206Sdd ds = dk->dk_ruleset; 252100206Sdd error = devfs_rule_delete(&dk); 253100206Sdd devfs_ruleset_reap(&ds); 254100206Sdd break; 255100206Sdd case DEVFSIO_RGETNEXT: 256100206Sdd dr = (struct devfs_rule *)data; 257100206Sdd error = devfs_rule_input(dr, dm); 258100206Sdd if (error != 0) 259100206Sdd goto out; 260100206Sdd /* 261100206Sdd * We can't use devfs_rule_byid() here since that 262100206Sdd * requires the rule specified to exist, but we want 263100206Sdd * getnext(N) to work whether there is a rule N or not 264100206Sdd * (specifically, getnext(0) must work, but we should 265100206Sdd * never have a rule 0 since the add command 266100206Sdd * interprets 0 to mean "auto-number"). 267100206Sdd */ 268100206Sdd ds = devfs_ruleset_bynum(rid2rsn(dr->dr_id)); 269100206Sdd if (ds == NULL) { 270100206Sdd error = ENOENT; 271100206Sdd goto out; 272100206Sdd } 273100206Sdd rnum = rid2rn(dr->dr_id); 274100206Sdd SLIST_FOREACH(dk, &ds->ds_rules, dk_list) { 275100206Sdd if (rid2rn(dk->dk_rule.dr_id) > rnum) 276100206Sdd break; 277100206Sdd } 278100206Sdd if (dk == NULL) { 279100206Sdd error = ENOENT; 280100206Sdd goto out; 281100206Sdd } 282100206Sdd memcpy(dr, &dk->dk_rule, sizeof(*dr)); 283100206Sdd error = 0; 284100206Sdd break; 285100206Sdd case DEVFSIO_SUSE: 286100206Sdd rsnum = *(devfs_rsnum *)data; 287100206Sdd error = devfs_ruleset_use(rsnum, dm); 288100206Sdd break; 289100206Sdd case DEVFSIO_SAPPLY: 290100206Sdd rsnum = *(devfs_rsnum *)data; 291100206Sdd rsnum = rid2rsn(devfs_rid_input(mkrid(rsnum, 0), dm)); 292100206Sdd ds = devfs_ruleset_bynum(rsnum); 293100206Sdd if (ds == NULL) { 294100206Sdd error = ESRCH; 295100206Sdd goto out; 296100206Sdd } 297100206Sdd devfs_ruleset_applydm(ds, dm); 298100206Sdd error = 0; 299100206Sdd break; 300100206Sdd case DEVFSIO_SGETNEXT: 301100206Sdd rsnum = *(devfs_rsnum *)data; 302100206Sdd SLIST_FOREACH(ds, &devfs_rulesets, ds_list) { 303100206Sdd if (ds->ds_number > rsnum) 304100206Sdd break; 305100206Sdd } 306100206Sdd if (ds == NULL) 307100206Sdd error = ENOENT; 308100206Sdd else { 309100206Sdd *(devfs_rsnum *)data = ds->ds_number; 310100206Sdd error = 0; 311100206Sdd } 312100206Sdd break; 313100206Sdd default: 314100206Sdd error = ENOIOCTL; 315100206Sdd break; 316100206Sdd } 317100206Sdd 318100206Sddout: 319150150Sphk sx_xunlock(&sx_rules); 320100206Sdd return (error); 321100206Sdd} 322100206Sdd 323100206Sdd/* 324100206Sdd * Called to initialize dm_ruleset when there is a new mount-point. 325100206Sdd */ 326100206Sddvoid 327100206Sdddevfs_rules_newmount(struct devfs_mount *dm, struct thread *td) 328100206Sdd{ 329100206Sdd struct devfs_ruleset *ds; 330100206Sdd 331100206Sdd /* 332100206Sdd * We can't use devfs_ruleset_use() since it will try to 333100206Sdd * decrement the refcount for the old ruleset, and there is no 334100206Sdd * old ruleset. Making some value of ds_ruleset "special" to 335100206Sdd * mean "don't decrement refcount" is uglier than this. 336100206Sdd */ 337150150Sphk sx_slock(&sx_rules); 338100206Sdd ds = devfs_ruleset_bynum(0); 339100206Sdd KASSERT(ds != NULL, ("no ruleset 0")); 340100206Sdd ++ds->ds_refcount; 341100206Sdd dm->dm_ruleset = 0; 342150150Sphk sx_sunlock(&sx_rules); 343100206Sdd} 344100206Sdd 345100206Sdd/* 346100206Sdd * Adjust the rule identifier to use the ruleset of dm if one isn't 347100206Sdd * explicitly specified. 348100206Sdd * 349100206Sdd * Note that after this operation, rid2rsn(rid) might still be 0, and 350100206Sdd * that's okay; ruleset 0 is a valid ruleset, but when it's read in 351100206Sdd * from the userland, it means "current ruleset for this mount-point". 352100206Sdd */ 353100206Sddstatic devfs_rid 354100206Sdddevfs_rid_input(devfs_rid rid, struct devfs_mount *dm) 355100206Sdd{ 356100206Sdd 357100206Sdd if (rid2rsn(rid) == 0) 358100206Sdd return (mkrid(dm->dm_ruleset, rid2rn(rid))); 359100206Sdd else 360100206Sdd return (rid); 361100206Sdd} 362100206Sdd 363100206Sdd/* 364100206Sdd * Apply dk to de and everything under de. 365100206Sdd * 366100206Sdd * XXX: This method needs a function call for every nested 367100206Sdd * subdirectory in a devfs mount. If we plan to have many of these, 368100206Sdd * we might eventually run out of kernel stack space. 369100206Sdd */ 370100206Sddstatic void 371100206Sdddevfs_rule_applyde_recursive(struct devfs_krule *dk, struct devfs_dirent *de) 372100206Sdd{ 373100206Sdd struct devfs_dirent *de2; 374100206Sdd 375150147Sphk TAILQ_FOREACH(de2, &de->de_dlist, de_list) 376100206Sdd devfs_rule_applyde_recursive(dk, de2); 377150147Sphk devfs_rule_run(dk, de, devfs_rule_depth); 378100206Sdd} 379100206Sdd 380100206Sdd/* 381100206Sdd * Apply dk to all entires in dm. 382100206Sdd */ 383100206Sddstatic void 384100206Sdddevfs_rule_applydm(struct devfs_krule *dk, struct devfs_mount *dm) 385100206Sdd{ 386100206Sdd 387149107Sphk devfs_rule_applyde_recursive(dk, dm->dm_rootdir); 388100206Sdd} 389100206Sdd 390100206Sdd/* 391100206Sdd * Automatically select a number for a new rule in ds, and write the 392100206Sdd * result into rnump. 393100206Sdd */ 394100206Sddstatic int 395100206Sdddevfs_rule_autonumber(struct devfs_ruleset *ds, devfs_rnum *rnump) 396100206Sdd{ 397100206Sdd struct devfs_krule *dk; 398100206Sdd 399100206Sdd /* Find the last rule. */ 400100206Sdd SLIST_FOREACH(dk, &ds->ds_rules, dk_list) { 401100206Sdd if (SLIST_NEXT(dk, dk_list) == NULL) 402100206Sdd break; 403100206Sdd } 404100206Sdd if (dk == NULL) 405100206Sdd *rnump = 100; 406100206Sdd else { 407100206Sdd *rnump = rid2rn(dk->dk_rule.dr_id) + 100; 408100206Sdd /* Detect overflow. */ 409100206Sdd if (*rnump < rid2rn(dk->dk_rule.dr_id)) 410100206Sdd return (ERANGE); 411100206Sdd } 412100206Sdd KASSERT(devfs_rule_byid(mkrid(ds->ds_number, *rnump)) == NULL, 413100206Sdd ("autonumbering resulted in an already existing rule")); 414100206Sdd return (0); 415100206Sdd} 416100206Sdd 417100206Sdd/* 418100206Sdd * Find a krule by id. 419100206Sdd */ 420100206Sddstatic struct devfs_krule * 421100206Sdddevfs_rule_byid(devfs_rid rid) 422100206Sdd{ 423100206Sdd struct devfs_ruleset *ds; 424100206Sdd struct devfs_krule *dk; 425100206Sdd devfs_rnum rn; 426100206Sdd 427100206Sdd rn = rid2rn(rid); 428100206Sdd ds = devfs_ruleset_bynum(rid2rsn(rid)); 429100206Sdd if (ds == NULL) 430100206Sdd return (NULL); 431100206Sdd SLIST_FOREACH(dk, &ds->ds_rules, dk_list) { 432100206Sdd if (rid2rn(dk->dk_rule.dr_id) == rn) 433100206Sdd return (dk); 434100206Sdd else if (rid2rn(dk->dk_rule.dr_id) > rn) 435100206Sdd break; 436100206Sdd } 437100206Sdd return (NULL); 438100206Sdd} 439100206Sdd 440100206Sdd/* 441100206Sdd * Remove dkp from any lists it may be on and remove memory associated 442100206Sdd * with it. 443100206Sdd */ 444100206Sddstatic int 445100206Sdddevfs_rule_delete(struct devfs_krule **dkp) 446100206Sdd{ 447100206Sdd struct devfs_krule *dk = *dkp; 448100206Sdd struct devfs_ruleset *ds; 449100206Sdd 450100206Sdd if (dk->dk_rule.dr_iacts & DRA_INCSET) { 451100206Sdd ds = devfs_ruleset_bynum(dk->dk_rule.dr_incset); 452100206Sdd KASSERT(ds != NULL, ("DRA_INCSET but bad dr_incset")); 453100206Sdd --ds->ds_refcount; 454100206Sdd devfs_ruleset_reap(&ds); 455100206Sdd } 456100206Sdd SLIST_REMOVE(&dk->dk_ruleset->ds_rules, dk, devfs_krule, dk_list); 457100206Sdd free(dk, M_DEVFS); 458100206Sdd *dkp = NULL; 459100206Sdd return (0); 460100206Sdd} 461100206Sdd 462100206Sdd/* 463130585Sphk * Get a struct cdev *corresponding to de so we can try to match rules based 464130585Sphk * on it. If this routine returns NULL, there is no struct cdev *associated 465100206Sdd * with the dirent (symlinks and directories don't have dev_ts), and 466100206Sdd * the caller should assume that any critera dependent on a dev_t 467100206Sdd * don't match. 468100206Sdd */ 469130585Sphkstatic struct cdev * 470100206Sdddevfs_rule_getdev(struct devfs_dirent *de) 471100206Sdd{ 472130585Sphk struct cdev **devp, *dev; 473100206Sdd 474100206Sdd devp = devfs_itod(de->de_inode); 475100206Sdd if (devp != NULL) 476100206Sdd dev = *devp; 477100206Sdd else 478100206Sdd dev = NULL; 479130585Sphk /* If we think this dirent should have a struct cdev *, alert the user. */ 480100206Sdd if (dev == NULL && de->de_dirent->d_type != DT_LNK && 481100206Sdd de->de_dirent->d_type != DT_DIR) 482130585Sphk printf("Warning: no struct cdev *for %s\n", de->de_dirent->d_name); 483100206Sdd return (dev); 484100206Sdd} 485100206Sdd 486100206Sdd/* 487100206Sdd * Do what we need to do to a rule that we just loaded from the 488100206Sdd * userland. In particular, we need to check the magic, and adjust 489100206Sdd * the ruleset appropriate if desired. 490100206Sdd */ 491100206Sddstatic int 492100206Sdddevfs_rule_input(struct devfs_rule *dr, struct devfs_mount *dm) 493100206Sdd{ 494100206Sdd 495100206Sdd if (dr->dr_magic != DEVFS_MAGIC) 496100206Sdd return (ERPCMISMATCH); 497100206Sdd dr->dr_id = devfs_rid_input(dr->dr_id, dm); 498100206Sdd return (0); 499100206Sdd} 500100206Sdd 501100206Sdd/* 502100206Sdd * Import dr into the appropriate place in the kernel (i.e., make a 503100206Sdd * krule). The value of dr is copied, so the pointer may be destroyed 504100206Sdd * after this call completes. 505100206Sdd */ 506100206Sddstatic int 507100206Sdddevfs_rule_insert(struct devfs_rule *dr) 508100206Sdd{ 509100206Sdd struct devfs_ruleset *ds, *dsi; 510100206Sdd struct devfs_krule *k1, *k2; 511100206Sdd struct devfs_krule *dk; 512100206Sdd devfs_rsnum rsnum; 513100206Sdd devfs_rnum dkrn; 514100206Sdd int error; 515100206Sdd 516100206Sdd /* 517100206Sdd * This stuff seems out of place here, but we want to do it as 518100206Sdd * soon as possible so that if it fails, we don't have to roll 519100206Sdd * back any changes we already made (e.g., ruleset creation). 520100206Sdd */ 521100206Sdd if (dr->dr_iacts & DRA_INCSET) { 522100206Sdd dsi = devfs_ruleset_bynum(dr->dr_incset); 523100206Sdd if (dsi == NULL) 524100206Sdd return (ESRCH); 525100206Sdd } else 526100206Sdd dsi = NULL; 527100206Sdd 528100206Sdd rsnum = rid2rsn(dr->dr_id); 529100206Sdd ds = devfs_ruleset_bynum(rsnum); 530100206Sdd if (ds == NULL) 531100206Sdd ds = devfs_ruleset_create(rsnum); 532100206Sdd if (ds->ds_flags & DS_IMMUTABLE) 533100206Sdd return (EIO); 534100206Sdd dkrn = rid2rn(dr->dr_id); 535100206Sdd if (dkrn == 0) { 536100206Sdd error = devfs_rule_autonumber(ds, &dkrn); 537100206Sdd if (error != 0) 538100206Sdd return (error); 539100206Sdd } 540100206Sdd 541111119Simp dk = malloc(sizeof(*dk), M_DEVFS, M_WAITOK); 542100206Sdd dk->dk_ruleset = ds; 543100206Sdd if (dsi != NULL) 544100206Sdd ++dsi->ds_refcount; 545100206Sdd /* XXX: Inspect dr? */ 546100206Sdd memcpy(&dk->dk_rule, dr, sizeof(*dr)); 547100206Sdd dk->dk_rule.dr_id = mkrid(rid2rsn(dk->dk_rule.dr_id), dkrn); 548100206Sdd 549100206Sdd k1 = SLIST_FIRST(&ds->ds_rules); 550100206Sdd if (k1 == NULL || rid2rn(k1->dk_rule.dr_id) > dkrn) 551100206Sdd SLIST_INSERT_HEAD(&ds->ds_rules, dk, dk_list); 552100206Sdd else { 553100206Sdd SLIST_FOREACH(k1, &ds->ds_rules, dk_list) { 554100206Sdd k2 = SLIST_NEXT(k1, dk_list); 555100206Sdd if (k2 == NULL || rid2rn(k2->dk_rule.dr_id) > dkrn) { 556100206Sdd SLIST_INSERT_AFTER(k1, dk, dk_list); 557100206Sdd break; 558100206Sdd } 559100206Sdd } 560100206Sdd } 561100206Sdd 562100206Sdd return (0); 563100206Sdd} 564100206Sdd 565100206Sdd/* 566100206Sdd * Determine whether dk matches de. Returns 1 if dk should be run on 567100206Sdd * de; 0, otherwise. 568100206Sdd */ 569100206Sddstatic int 570100206Sdddevfs_rule_match(struct devfs_krule *dk, struct devfs_dirent *de) 571100206Sdd{ 572100206Sdd struct devfs_rule *dr = &dk->dk_rule; 573130585Sphk struct cdev *dev; 574100206Sdd 575100206Sdd dev = devfs_rule_getdev(de); 576100206Sdd /* 577100206Sdd * At this point, if dev is NULL, we should assume that any 578100206Sdd * criteria that depend on it don't match. We should *not* 579100206Sdd * just ignore them (i.e., act like they weren't specified), 580100206Sdd * since that makes a rule that only has criteria dependent on 581130585Sphk * the struct cdev *match all symlinks and directories. 582100206Sdd * 583100206Sdd * Note also that the following tests are somewhat reversed: 584100206Sdd * They're actually testing to see whether the condition does 585100206Sdd * *not* match, since the default is to assume the rule should 586100206Sdd * be run (such as if there are no conditions). 587135727Sphk * 588135727Sphk * XXX: lacks threadref on dev 589100206Sdd */ 590100206Sdd if (dr->dr_icond & DRC_DSWFLAGS) 591100206Sdd if (dev == NULL || 592100206Sdd (dev->si_devsw->d_flags & dr->dr_dswflags) == 0) 593150147Sphk return (0); 594100206Sdd if (dr->dr_icond & DRC_PATHPTRN) 595100206Sdd if (!devfs_rule_matchpath(dk, de)) 596150147Sphk return (0); 597100206Sdd 598100206Sdd return (1); 599100206Sdd} 600100206Sdd 601100206Sdd/* 602100206Sdd * Determine whether dk matches de on account of dr_pathptrn. 603100206Sdd */ 604100206Sddstatic int 605100206Sdddevfs_rule_matchpath(struct devfs_krule *dk, struct devfs_dirent *de) 606100206Sdd{ 607100206Sdd struct devfs_rule *dr = &dk->dk_rule; 608100206Sdd char *pname; 609130585Sphk struct cdev *dev; 610100206Sdd 611100206Sdd dev = devfs_rule_getdev(de); 612100206Sdd if (dev != NULL) 613100206Sdd pname = dev->si_name; 614124798Scperciva else if (de->de_dirent->d_type == DT_LNK || 615124804Scperciva de->de_dirent->d_type == DT_DIR) 616109090Sdd pname = de->de_dirent->d_name; 617100206Sdd else 618100206Sdd return (0); 619100206Sdd KASSERT(pname != NULL, ("devfs_rule_matchpath: NULL pname")); 620100206Sdd 621104653Sdd return (fnmatch(dr->dr_pathptrn, pname, 0) == 0); 622100206Sdd} 623100206Sdd 624100206Sdd/* 625100206Sdd * Run dk on de. 626100206Sdd */ 627100206Sddstatic void 628150147Sphkdevfs_rule_run(struct devfs_krule *dk, struct devfs_dirent *de, unsigned depth) 629100206Sdd{ 630100206Sdd struct devfs_rule *dr = &dk->dk_rule; 631100206Sdd struct devfs_ruleset *ds; 632100206Sdd 633150147Sphk if (!devfs_rule_match(dk, de)) 634150147Sphk return; 635100206Sdd if (dr->dr_iacts & DRA_BACTS) { 636100206Sdd if (dr->dr_bacts & DRB_HIDE) 637100206Sdd de->de_flags |= DE_WHITEOUT; 638100206Sdd if (dr->dr_bacts & DRB_UNHIDE) 639100206Sdd de->de_flags &= ~DE_WHITEOUT; 640100206Sdd } 641100206Sdd if (dr->dr_iacts & DRA_UID) 642100206Sdd de->de_uid = dr->dr_uid; 643100206Sdd if (dr->dr_iacts & DRA_GID) 644100206Sdd de->de_gid = dr->dr_gid; 645100206Sdd if (dr->dr_iacts & DRA_MODE) 646100206Sdd de->de_mode = dr->dr_mode; 647100206Sdd if (dr->dr_iacts & DRA_INCSET) { 648150147Sphk /* 649150147Sphk * XXX: we should tell the user if the depth is exceeded here 650150147Sphk * XXX: but it is not obvious how to. A return value will 651150147Sphk * XXX: not work as this is called when devices are created 652150147Sphk * XXX: long time after the rules were instantiated. 653150147Sphk * XXX: a printf() would probably give too much noise, or 654150147Sphk * XXX: DoS the machine. I guess a a rate-limited message 655150147Sphk * XXX: might work. 656150147Sphk */ 657150147Sphk if (depth > 0) { 658150147Sphk ds = devfs_ruleset_bynum(dk->dk_rule.dr_incset); 659150147Sphk KASSERT(ds != NULL, ("DRA_INCSET but bad dr_incset")); 660150147Sphk devfs_ruleset_applyde(ds, de, depth - 1); 661150147Sphk } 662100206Sdd } 663100206Sdd} 664100206Sdd 665100206Sdd/* 666100206Sdd * Apply all the rules in ds to de. 667100206Sdd */ 668100206Sddstatic void 669150147Sphkdevfs_ruleset_applyde(struct devfs_ruleset *ds, struct devfs_dirent *de, unsigned depth) 670100206Sdd{ 671100206Sdd struct devfs_krule *dk; 672100206Sdd 673150147Sphk SLIST_FOREACH(dk, &ds->ds_rules, dk_list) 674150147Sphk devfs_rule_run(dk, de, depth); 675100206Sdd} 676100206Sdd 677100206Sdd/* 678100206Sdd * Apply all the rules in ds to all the entires in dm. 679100206Sdd */ 680100206Sddstatic void 681100206Sdddevfs_ruleset_applydm(struct devfs_ruleset *ds, struct devfs_mount *dm) 682100206Sdd{ 683100206Sdd struct devfs_krule *dk; 684100206Sdd 685100206Sdd /* 686100206Sdd * XXX: Does it matter whether we do 687100206Sdd * 688100206Sdd * foreach(dk in ds) 689100206Sdd * foreach(de in dm) 690100206Sdd * apply(dk to de) 691100206Sdd * 692100206Sdd * as opposed to 693100206Sdd * 694100206Sdd * foreach(de in dm) 695100206Sdd * foreach(dk in ds) 696100206Sdd * apply(dk to de) 697100206Sdd * 698100206Sdd * The end result is obviously the same, but does the order 699100206Sdd * matter? 700100206Sdd */ 701100206Sdd SLIST_FOREACH(dk, &ds->ds_rules, dk_list) { 702100206Sdd devfs_rule_applydm(dk, dm); 703100206Sdd } 704100206Sdd} 705100206Sdd 706100206Sdd/* 707100206Sdd * Find a ruleset by number. 708100206Sdd */ 709100206Sddstatic struct devfs_ruleset * 710100206Sdddevfs_ruleset_bynum(devfs_rsnum rsnum) 711100206Sdd{ 712100206Sdd struct devfs_ruleset *ds; 713100206Sdd 714100206Sdd SLIST_FOREACH(ds, &devfs_rulesets, ds_list) { 715100206Sdd if (ds->ds_number == rsnum) 716100206Sdd return (ds); 717100206Sdd } 718100206Sdd return (NULL); 719100206Sdd} 720100206Sdd 721100206Sdd/* 722100206Sdd * Create a new ruleset. 723100206Sdd */ 724100206Sddstatic struct devfs_ruleset * 725100206Sdddevfs_ruleset_create(devfs_rsnum rsnum) 726100206Sdd{ 727100206Sdd struct devfs_ruleset *s1, *s2; 728100206Sdd struct devfs_ruleset *ds; 729100206Sdd 730100206Sdd KASSERT(devfs_ruleset_bynum(rsnum) == NULL, 731100206Sdd ("creating already existent ruleset %d", rsnum)); 732100206Sdd 733111119Simp ds = malloc(sizeof(*ds), M_DEVFS, M_WAITOK | M_ZERO); 734100206Sdd ds->ds_number = rsnum; 735100206Sdd ds->ds_refcount = ds->ds_flags = 0; 736100206Sdd SLIST_INIT(&ds->ds_rules); 737100206Sdd 738100206Sdd s1 = SLIST_FIRST(&devfs_rulesets); 739100206Sdd if (s1 == NULL || s1->ds_number > rsnum) 740100206Sdd SLIST_INSERT_HEAD(&devfs_rulesets, ds, ds_list); 741100206Sdd else { 742100206Sdd SLIST_FOREACH(s1, &devfs_rulesets, ds_list) { 743100206Sdd s2 = SLIST_NEXT(s1, ds_list); 744100206Sdd if (s2 == NULL || s2->ds_number > rsnum) { 745100206Sdd SLIST_INSERT_AFTER(s1, ds, ds_list); 746100206Sdd break; 747100206Sdd } 748100206Sdd } 749100206Sdd } 750100206Sdd 751100206Sdd return (ds); 752100206Sdd} 753100206Sdd 754100206Sdd/* 755100206Sdd * Remove a ruleset form the system. The ruleset specified must be 756100206Sdd * empty and not in use. 757100206Sdd */ 758100206Sddstatic void 759100206Sdddevfs_ruleset_destroy(struct devfs_ruleset **dsp) 760100206Sdd{ 761100206Sdd struct devfs_ruleset *ds = *dsp; 762100206Sdd 763100206Sdd KASSERT(SLIST_EMPTY(&ds->ds_rules), ("destroying non-empty ruleset")); 764100206Sdd KASSERT(ds->ds_refcount == 0, ("destroying busy ruleset")); 765100206Sdd KASSERT((ds->ds_flags & DS_IMMUTABLE) == 0, 766100206Sdd ("destroying immutable ruleset")); 767100206Sdd 768100206Sdd SLIST_REMOVE(&devfs_rulesets, ds, devfs_ruleset, ds_list); 769100206Sdd free(ds, M_DEVFS); 770100206Sdd *dsp = NULL; 771100206Sdd} 772100206Sdd 773100206Sdd/* 774100206Sdd * Remove a ruleset from the system if it's empty and not used 775100206Sdd * anywhere. This should be called after every time a rule is deleted 776100206Sdd * from this ruleset or the reference count is decremented. 777100206Sdd */ 778100206Sddstatic void 779100206Sdddevfs_ruleset_reap(struct devfs_ruleset **dsp) 780100206Sdd{ 781100206Sdd struct devfs_ruleset *ds = *dsp; 782100206Sdd 783100206Sdd if (SLIST_EMPTY(&ds->ds_rules) && ds->ds_refcount == 0) { 784100206Sdd devfs_ruleset_destroy(&ds); 785100206Sdd *dsp = ds; 786100206Sdd } 787100206Sdd} 788100206Sdd 789100206Sdd/* 790100206Sdd * Make rsnum the active ruleset for dm. 791100206Sdd */ 792100206Sddstatic int 793100206Sdddevfs_ruleset_use(devfs_rsnum rsnum, struct devfs_mount *dm) 794100206Sdd{ 795100206Sdd struct devfs_ruleset *cds, *ds; 796100206Sdd 797100206Sdd ds = devfs_ruleset_bynum(rsnum); 798100206Sdd if (ds == NULL) 799100206Sdd ds = devfs_ruleset_create(rsnum); 800100206Sdd cds = devfs_ruleset_bynum(dm->dm_ruleset); 801100206Sdd KASSERT(cds != NULL, ("mount-point has NULL ruleset")); 802100206Sdd 803100206Sdd /* These should probably be made atomic somehow. */ 804100206Sdd --cds->ds_refcount; 805100206Sdd ++ds->ds_refcount; 806100206Sdd dm->dm_ruleset = rsnum; 807100206Sdd 808100206Sdd devfs_ruleset_reap(&cds); 809100206Sdd return (0); 810100206Sdd} 811